DE 10 2004 011 586 A1 discloses a camshaft module with a module cover, two parallel camshafts being accommodated in the module cover. The camshafts comprise main shafts, and a number of displacement elements is accommodated on each main shaft. The displacement elements can have their axial position on the main shaft altered by actuators accommodated in the module cover, and therefore different cam tracks can be brought into contact with a tapping element for valve-control purposes. For example it is possible for the displacement elements to be displaced between two or three discrete axial positions, and the displacement elements are accommodated in bearing bridges which are part of the module cover. The main shaft serves merely for transmitting torque to the displacement elements, and therefore the multi-part camshaft, which is formed by the main shaft and the displacement elements, is mounted in the bearing bridges by the individual displacement elements, the main shaft being mounted in the accommodating passages of the displacement elements.
For the transmission of torque between the main shaft and the displacement elements, the main shaft comprises an external toothing arrangement, which is in engagement with an internal toothing arrangement in the accommodating passages. The displacement elements can thus be moved in an axially displaceable and rotationally fixed manner on the main shaft.
The displacement elements have cam tracks which, for operation of an internal combustion engine, have to be in a certain rotary orientation about the axis of the camshaft. The defined circumferential position of the cam tracks, in particular of the cam lobes, serves for activating the valves at the correct time, and if the camshaft comprises for example four displacement elements, then the otherwise identical displacement elements have to be arranged on the main shaft at different angular positions about the shaft axis in order to make it possible for the gas-exchange valves of the plurality of cylinders of the internal combustion engine to be activated at the correct control times.
The mounting (assembling) of the camshaft module takes place here in successive steps: first of all, the displacement elements, in particular all the displacement elements forming a camshaft, are arranged on the module cover. It has to be ensured here that the circumferential position of the displacement elements in relation to one another are already in a rotary orientation which is correct for the subsequent operation of the camshaft. The insertion of the displacement elements usually takes place manually or by a gripper which ensures the correct rotary orientation of the displacement elements. It is disadvantageous here that each individual displacement element has to be gripped differently in order for the necessary rotary orientation assigned to each displacement element to be ensured during arrangement in the module cover. Installation of the camshaft module is thus made more difficult and, in addition, is susceptible to error. A displacement element oriented incorrectly in the circumferential direction on the main shaft can result in serious damage when an internal combustion engine having such a camshaft module is subsequently started up.